Patent GB-1351224-A (GB)
Title: Elevator control apparatus
IPC: B66B1/18
Filed: 1971-07-01
Abstract: 1351224 Multi-car control system HITACHI Ltd 1 July 1971 [3 July 1970] 30883/71 Heading B8L In a three car elevator control system, serving ten floors, the cars being regarded as moving in a loop 1U-9U-10D-2D-1U, each car, for example car A, serves hall calls only at floors between a position ahead of it in the direction of travel by an amount dependent on its speed, the distance between it and the succeeding car, the number of passengers in it, the number of hall calls and the reciprocating cycle time, and a corresponding position ahead of the next car before it on the loop. Should a car call in another car, B or C, exist for any of the above floors, car A does not call at the floor in response to a hall call thereat. Alternatively, car A may respond to all hall calls for the above floors. All floors whose calls for service can be responded to by car A, at any moment, represent the instantaneous service zone of a car A. Operation of car A.-A position space detector DA receives car position signals FA, FB, FC representing the positions of the respective cars when at rest, or positions one, two, or three floors ahead of the respective cars for operation at low, medium or high speed respectively, there being one such signal for each car, floor and direction of motion (F1UA...F2DC) Fig. 2 (not shown), and by means of a ring circuit including OR gates, and INHIBIT elements controlled by the other two cars, deliver an analogue voltage SSA across (rA) proportional to the distance between car A and the succeeding car. In a position advance deciding device EA the signals, (SSA), Fig. 3 (not shown), (CWA) representing the number of passengers in the car, (RTT) representing the reciprocating cycle time, and NOHC) for the number of hall calls are combined to form a weighted average and compared with a plurality of preset voltages (V 1 -V 4 ) to give outputs (EOA-E4A) indicating that the effective position of car A is to be advanced 0, 1 ... 4 floors ahead of the position given by one of signals (F1UA ... F2DC). In the position advancing device GA, utilizing AND gates, Fig. 4 (not shown). The signals (EOA-E4A) and (F1UAF2DC) are selectively combined to give effective position signals (f1Ua-f9Ua), (f10Da-f2Da not shown). A ring circuit, Fig. 5a (not shown) emits enabling signals (1u-9u, 10d-2d) for each floor between the effective position of car A and that of the car ahead of A on the ring. If the input signals to the circuit are rearranged, Fig. 5b (not shown), the regions wherein the cars respond may overlap, see also Figs. 7b, 7c. The enabling signals pass to inhibit elements in service zone defining circuitry (#), one circuit for each floor on the loop, Fig. 5c (not shown), which also receives the hall calls and provides output signals (N10DA ...) to cause stopping of the car. Since each inhibit is disenabled by the presence of car calls in the other cars for its corresponding floor, the service zone of car A is all floors between its effective position and that of the car in front, excluding those floors for which car calls in another car exist. Hall calls for each floor in the service zone are stored in a memory, until cancelled by being answered. An informing device D1SA, see, also Figs. 6, 7 (not shown) displays the service zone of each car using indicator lamps. A simplified circuit, alternative to Fig. 5c; Fig. 5d (not shown) defines the service zone of car A without respect to car calls in the other cars.